Historically, logjams have been removed from rivers due to concerns of flooding, erosion, and destruction of property. However, new research has demonstrated that logjams have beneficial properties including generating pools that protect salmoniod spawing, propagule retention sites, and increasing biodiversity. For these reasons, engineered logjams are being introduced into rivers across the Northwest of the United States. To better identify the key components that enable logjams to create suitable habitat for salmonid fish, I am conducting physical experiments with model logjams. These experiments vary the dimensions and solid volume fraction of the log jam, and measure the velocity and turbulence in the wake. After characterizing the dimensional effects of the logjams, suggestions on which type of logjam is most suitable given what is known about fish preference are made.